Pancreatic cancer

Pancreatic cancer occurs when malignant cells develop in any part of the pancreas. This may affect how the pancreas works, including its exocrine or endocrine functions. About 70% of pancreatic cancers are found in the head of the pancreas.

Pancreatic cancer can spread to nearby lymph nodes, blood vessels or nerves, and to the lining of the abdomen (peritoneum). Cancer cells may also travel through the bloodstream to other parts of the body, such as the liver.

Learn more about:

• The pancreas
• What are the main types of pancreatic cancer?
• Who gets pancreatic cancer
• What causes pancreatic cancer
• How important are genetic factors?

The pancreas

The pancreas is a long, flat gland about 13–15 cm long that lies between your stomach and spine. It is divided into three parts:

• the large rounded end, called the head of the pancreas
• the middle part, known as the body
• the narrow end, called the tail.

A tube called the pancreatic duct connects the pancreas to the first part of the small bowel (duodenum). Another tube, called the common bile duct, joins with the pancreatic duct and connects the liver and gall bladder to the duodenum.

What the pancreas does

Exocrine function – The pancreas is part of the digestive system, which helps the body digest food and turn it into energy. Exocrine cells make pancreatic enzymes, which are digestive juices. The pancreatic duct carries these juices from the pancreas into the duodenum, where they help to break down food. Most of the pancreas is made up of exocrine tissue.

Endocrine function – The pancreas is also part of the endocrine system, a group of glands that makes the body’s hormones. Endocrine cells in the pancreas make hormones that control blood sugar levels, the amount of acid produced by the stomach, and how quickly food is absorbed. For example, the hormone insulin decreases the level of sugar in the blood, while the hormone glucagon increases it.

The pancreas in the body

What are the main types?

There are two main types of pancreatic cancer:

Exocrine tumours – These make up more than 95% of pancreatic cancers. The most common type, called an adenocarcinoma, starts in the cells lining the pancreatic duct. Less common types include adenosquamous carcinoma and undifferentiated carcinoma. The different types are named after the cells they start in. Learn more about treatment for exocrine tumours.

Pancreatic neuroendocrine tumours (NETs) – About 5% of pancreatic cancers are pancreatic NETs. These start in the endocrine cells. Pancreatic NETs are categorised as either non-hormone producing (non-functioning) or hormone producing (functioning). Learn more about treatment for pancreatic NETs.

Who gets pancreatic cancer?

About 3300 Australians are diagnosed with pancreatic cancer each year. More than 80% are over the age of 60. It is estimated to be the eleventh most common cancer in males and eighth most common in females in Australia during 2019.

What causes pancreatic cancer?

Research has shown that people with certain risk factors are more likely to develop pancreatic cancer. Known risk factors include:

• smoking (cigarette smokers are about twice as likely to develop pancreatic cancer as non-smokers)
• obesity
• ageing
• type 2 diabetes
• pancreatitis (long-term inflammation of the pancreas)
• certain types of cysts in the pancreatic duct known as intraductal papillary mucinous neoplasms (IPMNs) – these should be assessed by an appropriate specialist
• drinking too much alcohol
• family history and inherited conditions
• workplace exposure to some pesticides, dyes or chemicals.

How important are genetic factors?

Most people diagnosed with pancreatic cancer do not have a family history of the disease. About one in 10 people who develop pancreatic cancer have an inherited faulty gene that increases the risk of developing pancreatic cancer.

You may have an inherited faulty gene if:

• two or more of your close family members (such as a parent or sibling) have had pancreatic cancer
• there is a family history of a genetic condition, such as Peutz-Jeghers syndrome, the familial breast cancer genes (BRCA1 and BRCA2), familial atypical multiple mole melanoma (FAMMM) syndrome, Lynch syndrome and hereditary pancreatitis.

Some pancreatic NETs are caused by a rare inherited syndrome, such as multiple endocrine neoplasia type 1 (MEN1), neurofibromatosis (NF-1), Von Hippel-Lindau (VHL) disease or tuberous sclerosis. Genetic testing aims to detect faulty genes that may increase a person’s risk of developing some cancers. People with a strong family history of cancer can attend a family cancer clinic for genetic counselling and tests. For more information, talk to your doctor, local family cancer centre or Cancer Council 13 11 20.